Robin van Persie produced another moment of magic to underline why Roberto Mancini fears he will cost Manchester City their Premier League title.

Although Javier Hernandez also managed a smartly-taken double as Manchester United cruised past Wigan to preserve their seven-point lead at the top, it was Van Persie who stamped his class on proceedings.

His 18th goal of the season was one of his best, calmly stepping inside Ivan Ramis before firing into the corner with his supposedly weaker right-foot.

And as he tapped Danny Welbeck's square ball into an empty net in stoppage time, it means Van Persie has now scored eight goals in his last eight games, an even better strike-rate than the eight in 11 Eric Cantona managed in his 1996 one-man title drive.

Sir Alex Ferguson has already likened Van Persie to Cantona with the effect he is having on the entire United squad.

It is difficult to argue with that assessment, just as it is difficult to see Ferguson's squad tossing away their advantage as they did so uncharacteristically 12 months ago.

United's failure to get to grips with Wigan's three-man defence in the corresponding fixture last term that condemned them to a defeat which triggered that downward spiral which cost them the title last season.

And they were in no mood to be similarly exposed this time around.

Ferguson filled his midfield, denying Roberto Martinez's men the space to implement an intended passing game.

The Latics were forced into far more long balls than normal and though the first 25 minutes lacked penalty-box action, slowly United were draining the life out of their opponents.

The warning came when Ryan Giggs lifted a superb crossfield ball beyond Wigan's defence, which Hernandez reached, only to be correctly ruled offside as he beat Ali Al Habsi.

After one fresh air shot, Evra let fly with a low stinger which Al Habsi could not hold, allowing Hernandez to pounce from close range.

It was the Mexican's 11th goal of the season and his 30th overall in the Premier League for United. Remarkably, all 30 have come from inside the area.

With the visitors now turning the screw, Wigan desperately needed to reach the interval without sustaining further damage.

Van Persie ensured they did not make it.

Between them, Ferguson and Mancini have, over the past week, underlined the Dutchman's value to the Red Devils cause.

Brilliance is not hard to spot though.

And after a mix-up in midfield gifted United possession deep inside the Wigan half, the hosts could not afford Ivan Ramis' slip, which allowed Van Persie a couple of extra seconds to decide what to do with Hernandez's pass.

Ramis recovered his ground, only for Van Persie to step inside the defender and find the far corner with a right-footed effort of unerring accuracy.

It was the work of a true world-class talent.

There was little chance of United throwing away the advantage he gave them on New Year's Day.

Other than a wafer-thin offside call that went against Kone, who tapped home Franco di Santo's low cross, the visitors were completely dominant.

No-one could begrudge them their third, just after the hour, when Van Persie's free-kick deflected into Hernandez's path. And the striker was once again in the box as he delivered the first-time finish.

United's job was done, as Ferguson confirmed by withdrawing Michael Carrick, who more than anyone has drove himself into the ground for his team during this productive Festive programme, in which they have dropped just two points.

And to think three-quarters of the work has been done without Wayne Rooney, who is still to recover from the minor knee injury he suffered on Christmas Day.

With Shinji Kagawa also getting a valuable 20 minutes under his belt, United are in a position of strength, and fittingly Van Persie had the last word two minutes from time.